"With these updates - part of the millions of live transit schedule updates we process every day - you get instant access to the latest information right on Google Maps, making trip planning a cinch," said Google in a statement.

Seven New York subway lines - including 1, 2, 3, 4, 5, 6 and the Times Square / Grand Central Shuttle - now have live departure times listed, but the Metropolitan Transit Authority's other lines require an upgrade before data is available.

Metrorail riders in Washington are being served real-time service alerts on Google Maps, while bus and tram information is available in Salt Lake City.

Google is yet to announce whether similar features will be added to Google Maps in other territories.